From 23374a84c5f08e20ec2506a6322330d51f9134c5 Mon Sep 17 00:00:00 2001 From: Raphael Norwitz Date: Thu, 21 May 2020 05:00:29 +0000 Subject: [PATCH] Add vhost-user helper to get MemoryRegion data MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When setting the memory tables, qemu uses a memory region's userspace address to look up the region's MemoryRegion struct. Among other things, the MemoryRegion contains the region's offset and associated file descriptor, all of which need to be sent to the backend. With VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS, this logic will be needed in multiple places, so before feature support is added it should be moved to a helper function. This helper is also used to simplify the vhost_user_can_merge() function. Signed-off-by: Raphael Norwitz Message-Id: <1588533678-23450-3-git-send-email-raphael.norwitz@nutanix.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Reviewed-by: Marc-André Lureau --- hw/virtio/vhost-user.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index 2e0552dd74..442b0d650a 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -407,6 +407,18 @@ static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base, return 0; } +static MemoryRegion *vhost_user_get_mr_data(uint64_t addr, ram_addr_t *offset, + int *fd) +{ + MemoryRegion *mr; + + assert((uintptr_t)addr == addr); + mr = memory_region_from_host((void *)(uintptr_t)addr, offset); + *fd = memory_region_get_fd(mr); + + return mr; +} + static void vhost_user_fill_msg_region(VhostUserMemoryRegion *dst, struct vhost_memory_region *src) { @@ -433,10 +445,7 @@ static int vhost_user_fill_set_mem_table_msg(struct vhost_user *u, for (i = 0; i < dev->mem->nregions; ++i) { reg = dev->mem->regions + i; - assert((uintptr_t)reg->userspace_addr == reg->userspace_addr); - mr = memory_region_from_host((void *)(uintptr_t)reg->userspace_addr, - &offset); - fd = memory_region_get_fd(mr); + mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd); if (fd > 0) { if (track_ramblocks) { assert(*fd_num < VHOST_MEMORY_MAX_NREGIONS); @@ -1551,13 +1560,9 @@ static bool vhost_user_can_merge(struct vhost_dev *dev, { ram_addr_t offset; int mfd, rfd; - MemoryRegion *mr; - mr = memory_region_from_host((void *)(uintptr_t)start1, &offset); - mfd = memory_region_get_fd(mr); - - mr = memory_region_from_host((void *)(uintptr_t)start2, &offset); - rfd = memory_region_get_fd(mr); + (void)vhost_user_get_mr_data(start1, &offset, &mfd); + (void)vhost_user_get_mr_data(start2, &offset, &rfd); return mfd == rfd; }